A handheld device is a small computing device such as a smartphone or wearable device. A typical handheld device includes a combination of complex components that enable a variety of functions. For example, a smartphone can combine features of a personal computer operating system with features of a mobile phone, media player, gaming device, Global Positioning System (GPS) navigation device, and a digital camera. As handheld devices continue evolving to include additional technologies, the combination of electronic components that can be incorporated into the handheld devices is limited by the size of the handheld devices. As a result, handheld devices appear structurally cluttered with cameras, light sources, buttons, scroll wheels, and other appurtenances. For example, a handheld device can include a camera flash used to produce a flash of light that illuminates a scene when capturing an image of that scene. A typical flash generating component is an outward facing bulky structure that is at least partially integrated into an outer casing of the handheld device.
Depth sensing technology can be used to determine the location of the device, including a depth sensor, in relation to nearby objects or to generate a three-dimensional image of the device's environment. An example of depth sensing technology is a time-of-flight (ToF) system. A ToF system includes a light source and a camera. The light source emits light onto nearby objects. Light reflected off the surfaces of the objects can be captured by the camera. The time it takes for the light to travel from the light source and reflect back from an object to the camera is converted into a depth measurement (i.e., distance to the object), which can be processed to map physical surfaces in an environment and, if desired, to render a three-dimensional image of the environment. Although depth sensing technologies can expand the capabilities of handheld devices, depth sensors are bulky structures that further clutter the exterior appearance of the handheld devices. As a result, multi-functional handheld devices can include a combination of separate bulky structures such as a digital camera light source, a light source for a depth sensor, and a camera for a depth sensor, which are at least partially embedded in the exterior casings of the handheld devices. Accordingly, a need exists to expand the capabilities of handheld devices while minimizing the impact of additional bulky structures included in the handheld devices.